Exam|Complete with A+ Graded Answers
The temperature of concrete may be measured in a wall form. True or False
True
The sensor of the temperature measuring device shall be submerged a minimum of _____ in. into the
freshly mixed concrete.
3 in.
Portions of a composite sample shall be thoroughly remixed bfore beginning tests on the sample.
True or False?
True
The temperature measuring device shall have a capacity of measuring temperature of freshly mixed
concrete to +- _____ degrees F [+- _____ C] throughout a range of _____.
1 degree F, 30 degrees F to 120 F
The temperature measuring device shall be calibrated _____, or whenever there is a question of
_____.
Annually, accuracy
The temperature of concrete may be measured in a wheelbarrow. True or False?
True
A composite sample of concrete is required even if the only purpose for obtaining the sample is to
determine temperature. True or False?
False
What must be done to the sample container prior to sampling the concrete?
Dampen with water
What must be done to the concrete surrounding the temperature measuring device after the device is
submerged in the fresh concrete.
Gently press the concrete around the temperature measuring device at the surface of the concrete
How long must the temperature measuring device remain in the freshly mixed concrete?
At least 2 minutes but not more than 5 minutes
After the temperature of the concrete is read, what is required?
Reporting of temperature
The temperature of concrete is reported to the nearest _____ degrees F
1 degree F
, According to ASTM C1064, what is one reason to take the temperature of concrete?
Verify conformance to a specified requirement for temperature of concrete
A maximum temperature of freshly mixed concrete is specified in ASTM C1064. True or False?
False
This method covers sampling from four types of mixtures which are _____, _____, _____, and _____.
Stationary mixers, paving mixers, revolving drum mixers, and open top mixers
The maximum allowable time between obtaining the first and final portions of a composite sample is
_____ minutes.
15
The maximum elapsed time allowed between obtaining the final portion of the composite sample and
beginning the tests for slump, temperature, and air content is _____ minutes.
5
The molding of strength test specimens shall begin within _____ minutes after fabricating the
composite sample.
15
The concrete sample must be protected from sources of _____ and _____.
contamination and rapid evaporation
The minimum size sample for making strength test specimens is _____.
1ft^3
When sampling from a stationary mixer, the batch must be sampled at _____ or more regularly
spaced intervals during discharge of the middle portion of the batch
2
The composite sample for a paving mixer must represent a minimum of _____ different portions of
the batch of concrete taken from the pile after discharge.
5
When sampling from a revolving drum truck mixer, concrete must be sampled at a minimum of _____
regularly spaced intervals during discharge of the middle portion of this batch.
2
Concrete samples from a truck mixer must be obtained before any water or admixtures are added to
the mixer at the job site. True or False?
False
The composite samples from a truck mixer must be obtained from the _____ portion of the batch.
Middle